Service valve assembly having a stop-fill device and a liquid level indicating dial

ABSTRACT

A combination tank valve apparatus providing fluid flow control, overfill protection, and fluid level gauging for use on a storage tank for liquefied gas, the storage tank having an internally threaded outlet port. The apparatus includes a service valve having a body defining a tank connection, a valve seat, a valve outlet, and a pair of wrench flats. The apparatus also includes an overfill protection device mounted to the tank connection of the service valve and including a float, a shaft, a overfill valve, and a shaft magnet. The apparatus also includes a dial mounted on the body of the service valve and having a body, a dial magnet, and a pointer, the pointer being mounted on the dial magnet to rotate with the dial magnet and provide a visual indication of the liquid level within the tank.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationSer. No. 11/023,664 entitled Gauge Assembly Having a Stop-fill Valve,filed Jul. 28, 2005 which claims the benefit of U.S. ProvisionalApplication No. 60/538,279, entitled “Gauge Assembly”, filed on Jan. 22,2004 and U.S. Provisional Application No. 60/572,143, entitled “GaugeAssembly Having a Stop-fill Device”, filed on May 18, 2004, thedisclosures of which are incorporated herein by reference. Thisapplication also claims the benefit of U.S. Provisional Application Ser.No. 60/822,926, entitled “Service Valve Assembly Having a Stop-fillDevice and Magnetic Liquid Level Indicator,” filed Aug. 18, 2006, U.S.Provisional Application Ser. No. 60/822,921 entitled “Gauge Assemblyhaving a Stop-Fill Device and a Liquid Level Indicator,” filed Aug. 18,2006 and U.S. Provisional Application Ser. No. 60/822,928, entitled“Gauge Assembly Having a Stop-Fill Device and a Liquid Level IndicatingDial” filed Aug. 19, 2006, the disclosures of which are incorporatedherein by reference.

TECHNICAL FIELD

This disclosure relates to a device capable of providing an indicationof a fluid level in a tank and capable of transitioning a tank inletbetween a state where fluid-flow is prevented and a state wherefluid-flow is allowed.

BACKGROUND

There are many different types of containers, tanks, vessels, andcanisters that are used for storing fluids. For convenience, thisdocument will use the term “tank” throughout to refer to what could beany kind of container, vessel, canister, tank, or the like.

It is often desirable to allow for monitoring of the fluid level in atank, particularly in cases where the tank is such that the fluid cannotconveniently be visually inspected. For this reason, many tanks areprovided with devices for communicating a fluid level, for examplethrough the use of a fluid-level gauge that can provide an indication ofthe amount of fluid present in a tank. There are many known examples offluid level gauges that use a float or a capacitance to mechanicallyand/or electrically drive an indicator.

It is also desirable in some cases to provide a stop-fill device forpreventing a tank from being over-filled. Known stop-fill devicesinclude those intended to be used in tanks that require a fluid to passthrough an inlet valve in order to enter the tank. Typically suchstop-fill devices include a float that rides on the surface of the fluidin the tank. As fluid is added to the tank, the float rises to a certainlevel at which point it causes, for example by releasing a spring, theinlet valve to close. Once the inlet valve is closed, no additionalfluid can be added to the tank.

It is further desirable in some cases to allow the indicating dial ofthe level gauge to be removable from the tank-valve assembly. Forexample, tanks are commonly traded-in for refilling, and the ownerreturning an empty tank may wish to remove the dial and use it on thenewly filled tank. In other cases, the dial may be removed to preventdamage during storage or refilling.

SUMMARY

The present disclosure provides a single assembly capable of serving asa fluid-level gauge, a stop-fill device, or a combination of both.Included is a rotary function for both driving a dial and/or foractivating a valve, thus reducing cost and number of parts, as well asproviding a simplified operation.

According to one, a gauge assembly is provided that comprises a shaftthat rotates according to a change in fluid level, an indicator forproviding an indication of the fluid level based on a rotationalposition of the shaft, and a stop-fill assembly for transitioningbetween an open configuration and a closed configuration based on therotational position of the shaft.

The stop-fill assembly can include a valve shuttle that rotates inconjunction with the rotation of the shaft and moves between an openposition corresponding with said open configuration and a closedposition corresponding with said closed configuration based on therotational position of the shaft. The valve shuttle can include a flowsurface at an angle to the direction of fluid flow when fluid is flowinginto the tank such that the pressure of fluid flowing across the flowsurface assists in rotating the valve shuttle from the open position tothe closed position. The stop-fill assembly is designed taking intoconsideration the controlling pressure zones throughout the flow path.The flow surface in one embodiment also has two or more vanes for thepurpose of imparting rotational force to the stop-fill assembly. Thestop-fill assembly can include a valve body having a release slot, andthe valve shuttle can have a retaining rib that is positioned in therelease slot when the stop-fill assembly is in the closed configurationand is positioned out of the release slot when the stop-fill assembly isin the open position. The valve shuttle can have an upper shaft, and thegauge assembly can further comprise an indicator driving member forcoupling with the indicator in order to translate a rotational positionof the upper shaft into a fluid level. The valve shuttle can include ablocking member that blocks fluid flow when the valve shuttle is in theclosed position.

According to another, a method of gauging and controlling fluid flow isprovided that comprises the steps of rotating a shaft as fluid level ina tank changes, translating a rotational position of the shaft into afluid level, and transitioning a stop-fill assembly between an openconfiguration and a closed configuration based on the rotationalposition of the shaft.

According to another aspect, a gauge assembly is provided that comprisesa shaft that rotates according to a change in fluid level and astop-fill assembly having a valve shuttle that rotates in conjunctionwith the rotation of the shaft and moves between an open position and aclosed position. The valve shuttle can include a flow surface that is atan angle to the direction of fluid flow such that the pressure of fluidflowing across the flow surface assists in rotating the valve shuttlefrom the open position to the closed position. In one embodiment, theshuttle is provided with vanes in the flow path to impart rotationalforce to the valve shuttle.

According to another aspect, a combination overfill protection device,fluid level gauge, and service valve for use on a tank operable tocontain fluids and gases is provided. The service valve has a bodydefining a set of wrench flats, an input port, and a tank port. Theoverfill protection device has a float that rotates a shaft in responseto a change in fluid level, the shaft transitioning the overfillprotection device between opened and closed configurations and rotatinga magnet within the service valve body proximate the wrench flat. Agauge dial has a dial magnet housing sized to fit proximate to thewrench flat such that rotation of the magnet within the service valveactuates a dial magnet housed substantially in the dial magnet housing.

According to another aspect, a system for determining a fluid level in apressurizable container is provided that comprises a service valvehaving a set of wrench flats. A stop-fill device is interconnected withthe service valve and operable to rotate a first magnet inside theservice valve in proximity to the wrench flat in proportion to theamount of fluid in the pressurizable container. A dial assembly having adial face and a pointer is attached to a second dial magnet, the seconddial magnet housed in a magnet protrusion on a side of the dial faceopposite the pointer and operable to fit against the service valve suchthat the pointer moves on the dial face proportionately to the degree ofrotation of the first magnet inside the service valve.

In yet another embodiment, an overfill protection system for use withremovable magnetic dial assembly is provided. The system comprises aservice valve defining a recess, the recess dimensioned to receive atleast a potion of the magnetic dial assembly. A shaft providing a magnetextends into the service valve and in proximity to the recess, the shaftoperable to rotate the magnet in proportion to a level of fluid incontact with a float operably connected to the shaft. The system alsocomprises an overfill protection mechanism operating in response to therotation of the shaft and moving from an open state to a closed state asthe level of fluid in contact with the float increases.

In another embodiment, a system for determining a fluid level in apressurizable container is provided. The system includes a service valvehaving a set of wrench flats. A stop-fill device interconnected with theservice valve and operable to rotate a first magnet inside the servicevalve in proximity to the wrench flats in proportion to the amount offluid in the pressurizable container is provided. A dial assembly isalso provided having a dial face and a pointer attached to a second dialmagnet, the second dial magnet housed in a magnet protrusion on a sideof the dial face opposite the pointer, the magnet protrusion defining afeature that is operable to fit against the service valve such that thepointer moves on the dial face proportionately to the degree of rotationof the first magnet inside the service valve.

A method of filling a pressurizable tank having a cylindrical sidewalldefining a central axis extending longitudinally therethrough, agenerally semi-hemispherical bottom wall and, a generallysemi-hemispherical top wall includes positioning the tank with a centrallongitudinal axis of the tank oriented in a generally verticaldirection. Fluid is directed into the tank though a stop-fill assemblyincluding a shuttle body, a valve body and a float operatively connectedto the shuttle body. The stop-fill assembly is positioned partiallyinside the tank with the shuttle body operable to engage the valve bodyand block the flow of fluid into the tank. In an open configuration,release ribs of the shuttle body are positioned out of release slots ofthe valve body. The release ribs translate longitudinally into therelease slots when the stop-fill assembly closes such that the releaseribs are in the release slots when the stop-fill assembly is in theclosed configuration. Fluid flowing between the shuttle body and thevalve body is directed radially away from the central axis of thecylinder at a location above the float. The method further includesoperating the shuttle body with the float to engage the shuttle bodywith the valve body and block fluid flow into the tank when the fluidlevel in the tank reaches a predetermined level. The shuttle body isbiased in an open position with a spring such that the stop-fillassembly opens after the fill operation is complete and the pressureacross the valve body equalizes.

In one aspect, the method further includes connecting the service valveto a source of pressurized fluid, opening the service valve to admitfluid into the tank and closing the service valve when the fluid levelin the tank reaches the predetermined level. In another aspect, thefloat is connected to a counterbalance with a float arm having arotating connection with a shaft connected to the shuttle body, whereinthe step of operating the shuttle body with the float comprises rotatingthe shuttle body with the float arm to move the shuttle body intoengagement with the valve body. In another variation, the step ofdirecting the fluid radially away from the central axis of the cylinderfurther comprises directing the fluid through a least one port in thevalve body that extends radially away from a longitudinal axis of theshaft.

In one variation, the fluid level in the tank is displayed with a dialindicator operatively coupled to the float. The dial indicator may bepermanently or removable mounted on the service valve.

In yet another aspect, an overfill protection device for use with apressurizable tank having a cylindrical sidewall defining a central axisextending longitudinally therethrough, a generally semi-hemisphericalbottom wall and a generally semi-hemispherical top wall includes a floatadapted to float at the liquid/gas interface of a liquefied gas in thetank. A shaft operably connected to the float rotates in response tochanges in the position of the float and has an upper portion extendinginto the throat of a service valve mounted the tank. An overfill valveoperably connected to the shaft transitions between opened and closedconfigurations when the shaft rotates into a predetermined position. Theoverfill valve includes at least one outlet port extending radiallyrelative to the central axis of the tank such that fluid entering thetank through the overfill valve is directed radially outward away fromthe central axis of the tank.

In one variation, the device includes a float arm for mounting the floatand a counterbalance mounted on the float arm. The float arm isrotatably connected to the between the float and the counterbalance torotate the shaft in response to movement of the float. The float arm mayalso be is offset from a longitudinal axis of the float arm to increasethe sensitivity of the float.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure is illustrated by way of example and is notlimited by the figures of the accompanying drawings, in which likereference numbers indicate similar parts:

FIG. 1 shows a perspective view of a tank suitable for use with thepresent stop-fill device;

FIG. 2 shows a perspective view of a gauge assembly incorporating thepresent stop-fill device;

FIG. 3 is a perspective view of the stop-fill assembly included in thegauge assembly shown in FIG. 2;

FIG. 4 is an exploded view of the stop-fill assembly shown assembled inFIG. 3;

FIG. 5 is a perspective view of a valve shuttle included in thestop-fill assembly shown in FIGS. 3 and 4;

FIG. 6 is a perspective view of a valve body included in the stop-fillassembly shown in FIGS. 3 and 4;

FIG. 7 is an orthogonal view of the gauge assembly shown in FIG. 2 in analternate position;

FIG. 8 is an enlarged view of the area in FIG. 7 designated as 8;

FIG. 9 is a top view of the stop-fill assembly in a closed position;

FIG. 10 is a cross-sectional view of the stop-fill assembly taken alongsection X-X in FIG. 9;

FIG. 10A is a partial cross-sectional view of the stop-fill assemblytaken along section X-X in FIG. 9;

FIG. 11 is a cross-sectional view of the stop-fill assembly taken alongsection XI-XI in FIG. 9;

FIG. 11A is a partial cross-sectional view of the stop-fill assemblytaken along section XI-XI in FIG. 9;

FIG. 12 is an enlarged view of the area in FIG. 10 designated as 12;

FIG. 13 is a top view of the stop-fill assembly in an open position;

FIG. 14 is a cross-sectional view of the stop-fill assembly taken alongsection XIV-XIV in FIG. 13;

FIG. 14A is a partial cross-sectional view of the stop-fill assemblytaken along section XIV-XIV in FIG. 13;

FIG. 15 is a cross-sectional view of the stop-fill assembly taken alongsection XV-XV in FIG. 13;

FIG. 15A is a partial cross-sectional view of the stop-fill assemblytaken along section XV-XV in FIG. 13;

FIGS. 16A-D are perspective views of various valve shuttles havingvanes;

FIGS. 17A-D are perspective end views of the valve shuttles shown inFIGS. 16A-D;

FIG. 18A is a side view of one embodiment of a combination service valveassembly in accordance with aspects of the present disclosure;

FIG. 18B is a partial side view of the valve assembly of FIG. 18A withthe service valve removed to better illustrate features of the stop-filldevice;

FIG. 19A is an exploded view of a stop-fill assembly in accordance withaspects of the present disclosure;

FIG. 19B is a partial top view of the valve body of the stop-fillassembly of FIG. 19A;

FIG. 19C is a partial sectional and cutaway view of the shuttle body andvalve body of FIG. 19A;

FIG. 19D is a partial top view of an alternate valve body for thestop-fill assembly of FIG. 19A;

FIG. 19E is a partial sectional and cutaway view of an alternate shuttlebody and valve body for the stop-fill assembly of FIG. 19A;

FIG. 19F is a partial side view of an alternate float assembly for usein connection with the stop-fill assembly of FIG. 19A.

FIG. 19G is a partial sectional view illustrating the stop-fill assemblyof FIG. 19A positioned in a tank in accordance with aspects of thedisclosure;

FIG. 20A is a front view of one embodiment of a liquid level indicatingdial in accordance with aspects of the present disclosure;

FIG. 20B is a rear view of another embodiment of a liquid levelindicating dial in accordance with aspects of the present disclosure;

FIG. 20C is a side view of another embodiment of a liquid levelindicating dial in accordance with aspects of the present disclosure;

FIG. 20D is another rear view of another embodiment of a liquid levelindicating dial in accordance with aspects of the present disclosure;

FIG. 20E is another side view of another embodiment of a liquid levelindicating dial in accordance with aspects of the present disclosure;

FIG. 21 is a side view of one embodiment of a service valve inaccordance with aspects of the present disclosure;

FIG. 22 is a side view of another embodiment of a service valve inaccordance with aspects of the present disclosure;

FIGS. 23A-B are rear views with partial cutaway showing an upper portionof a combination service valve, a stop-fill assembly, and a removabledial in accordance with aspects of the present disclosure;

FIGS. 24A-B are rear views with partial cutaway showing an upper portionof a combination service valve, a stop-fill assembly, and a removabledial in accordance with aspects of the present disclosure;

FIG. 25 is a diagram illustrating one possible correlation between themagnetic field produced by an indicator magnet and a dial pointerreading according to aspects of the present disclosure;

FIG. 25A is a side view illustrating the spatial relationship between agauge magnet and a dial magnet in accordance with aspects of the presentdisclosure;

FIG. 26 is partial sectional, partial cut-away view of a combinationstop-fill assembly in accordance with aspects of the present disclosure;

FIG. 26A is a perspective view of the valve body and support member ofthe stop-fill assembly of FIG. 26;

FIG. 26B is a top view of the valve body of the stop-fill assembly ofFIG. 26;

FIG. 27 is an enlarged portion of FIG. 26 designated by dashed lines inFIG. 26;

FIG. 28 is a partial sectional view of the stop-fill assembly of FIG. 26taken along line 28-28′ of FIG. 26;

FIG. 29 is a partial sectional view of the stop-fill assembly of FIG. 26taken along line 29-29′ of FIG. 26;

FIG. 30 is a perspective view of the valve shuttle of the stop-fillassembly of FIG. 26;

FIG. 31 is a top view of the valve shuttle of FIG. 30; and

FIG. 32 is an enlarged view of the portion of FIG. 28 enclosed in dashedlines.

DETAILED DESCRIPTION

Various aspects and embodiments will now be described with reference tothe drawings. FIG. 1 shows a perspective view of a tank 100 having agauge assembly 110. FIG. 2 shows a perspective view of the gaugeassembly 110. It will be appreciated that the tank 100 is shown forexemplary purposes only and is in no way intended to limit the scope ofthe present disclosure.

The gauge assembly 110 includes a port 120 that is accessible fromoutside the tank 100. The port 120 allows fluid to be moved in and outof the tank 100. The gauge assembly 110 also includes an indicator 130for providing an indication of the fluid level in the tank 100. In thepresent embodiment, the indicator 130 is a dial-type indicator, but anytype of indicator could be used.

As shown in FIG. 2, the gauge assembly 110 includes a stop-fill assembly200, a support member 190, a vertical shaft 160 disposed within thesupport member 190, a float 140 and a float arm 150. The float 140 canbe made of close foam material, and the vertical shaft 160, the supportmember 190, and the float arm 150 can be made of any rigid material,including an acetal such as Delrin®. A distal end of the float arm 150is fixed to the float 140, and a proximal end of the float arm 150 isconnected to the vertical shaft 160 such that the float arm 150 isrotatable about the base of the vertical shaft 160. As the fluid levelin the tank 100 changes, the float 140 moves up or down with the fluidlevel causing the float arm 150 to rotate about the base of the supportmember 190. The float arm 150 is shown in an alternate position in FIG.7. Rotation of the float arm 150 about the base of the support member190 causes the vertical shaft 160 to rotate about the longitudinal axisof the vertical shaft 160. In the present embodiment, the rotation ofthe float arm 150 is translated to the rotation of the vertical shaft160 by a sector gear 170, fixed to the proximal end of the float arm 150that engages a pinion gear 180, fixed to the lower end of the verticalshaft 160.

The stop-fill assembly 200 is fixed to an upper end of the supportmember 190. FIG. 3 shows a perspective view of the stop-fill assembly200, and FIG. 4 shows an exploded view of the stop-fill assembly 200.The stop-fill assembly 200 includes a valve body 210 (also shown in FIG.6), a valve head 220, and a valve shuttle 230 (also shown in FIG. 5),all of which can be made of any rigid material, including an acetal suchas Delrin®.

The valve shuttle 230 has a shuttle body 290 that serves as a blockingmember for blocking fluid flow, an upper shaft 240 that extends upwardlyfrom the shuttle body 290 through the valve head 220, and a lower shaft280 that extends downwardly from the shuttle body 290. A magnet 270 thatserves as an indicator driving member is fixed to an upper end of theupper shaft 240 for driving the indicator 130. A tab 250 is formed inthe lower end of the lower shaft 280 for engaging with a slot 260 (seeFIG. 8) formed in an upper end of the vertical shaft 160 in order totransmit rotary motion of the vertical shaft 160 to the valve shuttle230. As the vertical shaft 160 rotates, the magnet 270 also rotates. Themagnet 160 is coupled with a dial 370 of the indicator 130 such that therotation of the magnet 270 causes rotation of the dial 370 according toknown methods. The lower shaft 280 also includes an opposing pair ofrelease ribs 320 for engaging with an opposing pair of release slots 330formed in the valve body 210 when the stop-fill assembly 200 is in aclosed position.

It is contemplated that an indicator other than the one used in thepresent embodiment can be used that does not require the presence of themagnet 270. For example, an indicator driving member such as an encodeddisk could be used in place of the magnet 270 and an indicator could beused that optically couples with the encoded disk to translate therotational position of the encoded disk into a fluid level. In fact, itis contemplated that any kind of indicator and/or indicator drivingmember can be used that translates the rotation of the upper shaft 240into a fluid level.

The stop-fill assembly 200 includes an optional valve o-ring 300 forassisting in sealing the shuttle body 290 to a seal surface 310 of thevalve body 210 when the stop-fill assembly is in the closed position. Aseal 340 can optionally be provided for assisting in sealing thejuncture between the valve head 220 and the valve body 210. Depending onhow the valve body 210 is attached to the valve head 220, the seal 340can be unnecessary, for example if the valve body 210 and valve head 220are welded together, for example by ultrasonic welding. A springretainer 350 is provided in a through-hole in the lower shaft 280 andextends from both sides of the lower shaft 280 in order to retain anupper end of a spring 360 (see FIG. 8). It will be appreciated that,instead of using a separate item as the spring retainer 350, the springretainer 350 can instead be integrally formed in the valve shuttle 230.

The stop-fill assembly 200 can transition between an open position and aclosed position. In the open position, fluid from the port 120 can flowthrough the stop-fill assembly 200, while in the closed position fluidfrom the port 120 is prevented from flowing through the stop-fillassembly 200. A top view of the stop-fill assembly 200 is provided inFIGS. 9 and 13, where FIG. 9 shows a top view of the stop-fill assembly200 when in the closed position, and FIG. 13 shows a top view of thestop-fill assembly 200 when in the open position. FIGS. 10 and 11 showcross-sectional views and FIGS. 10A and 11A show partial cross-sectionalviews of the closed position along section lines X-X and XI-XI,respectively, of FIG. 9, while FIGS. 14 and 15 provide cross-sectionalviews of the open position along section lines XIV-XIV and XV-XV,respectively, of FIG. 13.

In the open position, as shown in FIGS. 14 and 15 and in FIGS. 14A and15A, and under the pressure of incoming fluid from the port 120 pressingdownward on the shuttle body 290, the release ribs 320 of the valveshuttle 230 ride against the upper surface of the valve body 210. Thus,as best shown in FIG. 14, the release ribs 320 are what keep thestop-fill assembly 200 open against the force of a fluid flow from theport 120. When the gauge assembly 110 is in the empty position (i.e.,having the float arm 150 rotated to the position corresponding with anempty condition of the tank) the release ribs 320 are at 90 degreeangles to the slots, sitting on the upper surface of the valve body 210so that the valve shuttle 230 cannot go down. In this configuration,fluid from the port 120 travels downward through the space between theupper shaft 240 and the valve head 220, around the shuttle body 290across flow surfaces 380, 390, 395, then through fill ports 410 en routeto the inside of the tank 100.

As the vertical shaft 160 rotates due to the motion of the float arm150, the valve shuttle 230 rotates and eventually rotates to theposition shown in FIGS. 10 and 10A and FIGS. 11 and 11A where therelease ribs 320 line up with the release slots 330, which is best shownin FIG. 11. When this happens, the downward pressure of the fluid flow,which is sufficient to overcome the opposing pressure of the spring 360,causes the release ribs 320 to drop into the release slots 330 due tothe force from the fluid flow. As shown in FIGS. 10 and 12, the shuttlebody 290 acts as a blocking member since the contacting surfaces of theshuttle body 290 and the valve body 210 prevent fluid from travelingfrom the space above the shuttle body 290 to the fill ports 410 or intothe tank 100. The optional valve o-ring 300 assists in sealing thejunction between the shuttle body 290 to the valve body 210.

Once the stop-fill assembly 200 is in the closed position, filling ofthe tank 100 is halted and at some point the source of the incomingfluid is disconnected from the port 120 or the port 120 is closed. Atthis point, since there is no longer any pressure against the upper sideof the valve shuttle 230, the valve shuttle 230 is moved upward underthe force of the spring 360 so that the stop-fill assembly 200transitions to the open position. This allows for fluid to exit the tank100 by traveling back up through the stop-fill assembly 200 to the port120.

In the present embodiment, the total rotation of the float arm 150between full and empty fluid levels is approximately 100 degrees, whilethe total rotation necessary for moving the valve shuttle 230 betweenthe open position and the closed position is pinion gear 180 is close toa one to one relationship. However, it will be appreciated that theangle of the range of motion of the float arm 150 can vary, for examplebased on the size and shape of the tank 100, and the angle of the rangeof motion of the valve shuttle 230 can vary, for example based on therequirements of the indicator 130. Thus the relationship between thesector gear 170 and the pinion gear 180 can vary so long as therelationship is such that it allows the angle of the range of motion ofthe float arm 150 and the angle of the range of motion of the valveshuttle 230 needed at the dial 370 of the indicator 130 to coincide.

In some cases there may be relatively high pressures against the shuttlebody 290 due to the filling pressure and the fluid flow. The actualflotation or the buoyancy of the float 140 produces a relatively smalltorque, so friction between the release ribs 320 and the upper surfaceof the valve body 210 might be high and resist rotation of the valveshuttle 230. For this reason, it is desirable to keep the diameter ofrotation of the release ribs 320 as small as practical to reduce theresisting torque. Since the torque felt by the valve shuttle 230 istangential force times moment arm, reducing the moment arm (i.e.,diameter of rotation of the release ribs 320) reduces the resistingfriction torque. It is also desirable to form the valve shuttle 230,particularly the release ribs 320, and the valve body 210, particularlythe upper surface thereof, from a material having a low coefficient offriction against itself, for example an acetal such as Delrin®. Anotheroption is to provide a friction-reducing material (not shown), forexample a Teflon®. fill material, between the release ribs 320 and theupper surface of the valve body 210, that is made of a material having alow coefficient of friction.

In addition, the flow surfaces 380 of the shuttle body 290 are slantedsuch that when fluid flows across the flow surface 380 the pressure ofthe fluid against the slanted surface will tend to rotate the valveshuttle 230 in a predetermined direction (clockwise in the presentembodiment) to help overcome the friction between the release ribs 320and the upper surface of the valve body 210. Also, since fluid flow intothe tank 100 across the slanted flow surfaces 380 will tend to rotatethe valve shuttle 230 in a predetermined direction as the tank 100 isbeing filled, clearances are reduced or removed between portions ofvarious parts, such as between portions of the tab 250 and the slot 260and between portions of engaged teeth of the sector gear 170 and thepinion gear 180, while the tank 100 is being filled. For example, theslot 260 can be slightly wider than the thickness of the tab 250 toallow for the tab 250 to be longitudinally inserted and removed from theslot 260. As a consequence, the tab 250 would be free to rotate to somedegree while inserted in the slot 260. Therefore, if the valve shuttle230 is not provided with a slanted surface such as flow surface 380,turbulence from incoming fluid flowing across the valve shuttle 230could cause unpredictable rotational motion of the valve shuttle 230.However, since the fluid flow across flow surfaces 380 tends to rotatethe valve shuttle 230 in a predetermined direction, the tab 250 will berotated, in the predetermined direction, relative to the slot 260 at ornear a maximum degree allowed by the total clearance between the tab 250and the slot 260 such that portions of the tab 250 contact portions ofthe slot 260. That is, a clearance is reduced or eliminated betweenportions of the tab 250 and the slot 260 as fluid is flowing into thetank 100. It will be appreciated that a clearance between portions ofteeth of the sector gear 170 and the pinion gear 180 is also reduced oreliminated since the rotation of the valve shuttle 130 is transferred topush together engaging teeth of the pinion gear 180 and the sector gear170 as fluid is flowing into the tank 100. Thus, with the slanted flowsurface 380, clearances between portions of various parts are reduced oreliminated allowing a greater degree of accuracy to be achieved inpredicting the location of the release ribs 320 relative to the releaseslots 330 while the tank 100 is being filled.

The shuttle and valve can be designed by considering control of thepressure zones through the flow path of the valve. The valve ispreferably designed to create low pressure zones above the shuttle andhigh pressure zones below the shuttle. Such a design will tend to lessenthe total downward force on the shuttle thus reducing the frictionworking against the desired rotation of the shuttle. The area of flow atvarious points along the flow path can be plotted and the pressureprofile determined. Thus, the specific design of the chamber and theshuttle can be modified to change the pressure profile as desired.

In the event that smooth slanted flow surfaces 380 are insufficient toprovide the desired rotation force to valve shuttle 230 in apredetermined direction to help overcome the friction between thevarious portions of the valve shuttle which are in contact with thevalve body, vanes can be provided on the valve shuttle of apredetermined shape and size to impart the desired rotational force tothe valve shuttle in a predetermined direction. FIGS. 16A-D illustratedvarious configurations of vanes, and FIGS. 17A-D are end views of therespective figures in FIGS. 16A-D. Any desired shape of the vanes can beutilized, and while all of the illustrated vanes extend from the surfaceof the shuttle, it will be appreciated that vanes could be supplied inthe form of grooves in the shuttle. FIGS. 16A and 17A show vanes 400having a uniform thickness and having a substantially flat front sidesurface 402 and a substantially flat rear side (not shown). Vanes 400are set at a predetermined angle 406 to shuttle axis 408. FIGS. 16B and17B show vanes 411 in the shape of a curved plate of substantiallyuniform thickness and having a curved front side 412 and a curved rearside 414. The front and rear sides can be oriented such that they aresubstantially parallel to the shuttle axis 408. FIGS. 16C and 17Dillustrate vanes 420 having a substantially uniform thickness and havinga flat front side 422 and a flat rear side 424. The vanes have alongitudinal axis 426 which is perpendicular to the shuttle axis 408 andset off the shuttle axis a predetermined distance 428. FIGS. 16D and 17Dillustrate vanes 430 having a substantially uniform cross-section and acurved front side 432 and a curved rear side 434. The inner end 436 ofvanes 432 is adjacent to the shuttle axis 408 and surfaces of the frontand rear side 432 and 434 are parallel to axis 408. While the vanes havebeen illustrated having substantially uniform thickness, it will beappreciated by those skilled in the art that they may have non-uniformthickness. The base where the vanes attach to the shuttle can be thickerthan the other end. The flow of fluid across the vanes will assist inrotating the valve shuttle from the open position to the closedposition. The vanes can be shaped such that the thickness of the vanesvaries in the shape of an airfoil.

The spring 360 allows for the stop-fill assembly 200 to remain in theopen position when not under the pressure of incoming fluid. However, insome cases the pressure of fluid in the tank 100 is sufficient to causethe valve shuttle 230 to move to the open position when the port 120 isopen so that even without the spring 360 fluid can be removed from thetank 100.

It is contemplated that an arrangement other than the above embodimenthaving the float arm 10 can be used. One option is to use a spiral gaugehaving a float on the vertical shaft 160 where the vertical shaft 160has a ramp going up such that, as the float moves up and down thevertical shaft 160, the shaft 160 rotates.

It is also contemplated that the device could be modified to eliminatethe indicator or the stop-fill function. For example, the valve shuttle230 could be replaced with a shaft so that the gauge assembly drives theindicator 130 but does provide stop-fill functionality. As anotherexample, the indicator 130 and magnet 270 could be eliminated so thatthe gauge assembly has stop-fill functionality but not an indicator.

Referring now to FIGS. 18A and 18B, a side view of a combination servicevalve stop-fill assembly and liquid level indicator in accordance withadditional aspects of the present disclosure is shown. As will bedescribed, and as can be seen from FIGS. 18A and 18B, the combination1800 shares many parts and features that have been previously describedherein. A service valve assembly 1805 connects to a stop-fill assembly1900. A dial 2600 is also provided and interconnects with the servicevalve assembly 1805. In some embodiments the dial may be removable andreattach-able by the user, while in other embodiments the dial may bepermanently or semi-permanently affixed to the service valve. Theservice valve assembly 1805 provides a port 120 in a valve outlet 1802.The service valve assembly 1805 also provides port threads 1814. Theport threads 1814 may be used to interconnect the service valve assembly1805 with an external device such as a filling device or appliance. Atank connection 1820 is also provided for connecting with a tank such asthe tank 100 shown in FIG. 1. To aid in connection to the tank, the tankconnection 1820 may provide tank connection threads 1822. In someembodiments, the threads 1822 will mate with threads provided on thetank 100. Also shown in the embodiment of FIG. 18A is a service valveknob 1812. In some embodiments, the service valve knob 1812 may be usedto allow or restrict the flow of gas through the service valve assembly1805.

Referring still to FIGS. 18A and 18B, the stop-fill assembly 1900 mayfunction in a similar manner as those previously described. As best seenin FIG. 18B, an upper shaft 240 can be seen connecting to a magnet 270.A valve head 220 of the stop-fill assembly 1900 is provided with threads1910. The threads 1910 provide a secure means allowing the stop-fillassembly 1900 to connect with a service valve as will be describedfurther below. A support member 190 secures a rotatable vertical shaft160 that attaches to a pinion gear 180. The pinion gear 180 engages asector gear 170 which attaches to a float arm 150. As before, a float140 is provided at one end of the float arm 150. In the embodiment shownin FIG. 18A a counter balance 1825 is provided at the end of the floatarm 150 opposite the float 140. The counter balance 1825 may serve todecrease the resistance to movement that may be encountered internallyin the stop-fill assembly 1810. Additionally, as can be seen in FIG.18A, the counter-balance 1825 may serve to prevent an over rotation ofthe float arm 150 via its interference with the support member 190. Thevertical shaft 160 rotates in response to movement of the float 140. Therotation of the vertical shaft 160 drives the fluid stopping mechanismsof the stop-fill assembly 1900. Such mechanisms have been previouslydescribed with respect to other embodiments and therefore will not berepeated here. The vertical shaft 160 also provides rotation of a magnet270 that drives a dial as shown below. Although a geared mechanism isused to operatively connect the float arm to the shaft 160 in theillustrated embodiment, it will be appreciated that other knownmechanisms may be substituted in other embodiments.

FIG. 19A is an exploded view of another stop-fill assembly in accordancewith aspects of the present disclosure. The stop-fill assembly 1810 maybe used in a combination device such as those shown described herein.The stop-fill assembly 1810 is similar in some respects to the stop-fillassemblies previously described herein. A support member 190 is providedwith a vertical shaft 160 disposed within. A float arm 150 is connectedto the support member 190 so as to be able to rotate thereon. An eyelet2316 may be provided as a fastener between the support member 190 andthe float art 150. The float arm 150 is also connected at opposite endsto a float 140 and a counter balance 1825. Rotation of the float arm 150about the base of the support member 190 causes the vertical shaft 160to rotate about the longitudinal axis of the vertical shaft 160. Therotation of the float arm 150 may be translated to the rotation of thevertical shaft 160 by a sector gear 170, fixed to the proximal end ofthe float arm 150 that engages a pinion gear 180, fixed to the lower endof the vertical shaft 160. In other embodiments, other known methods oftranslating the motion of the float 140 to rotation of the shaft 160 maybe used instead of the geared arrangement.

The stop-fill assembly 1810 also includes a valve body 210 and a valvehead 220. A shuttle body 290 serves as a blocking member for blockingfluid flow. An upper shaft 240 extends upwardly from the shuttle body290 through the valve head 220. If desired, an eyelet 2311 may beprovided for increasing the durability or structural integrity of thevalve head 220. A magnet, 270 that serves as an indicator drivingmember, is fixed to an upper end of the upper shaft 240. A tab 250 isformed below the shuttle body 290 on a lower shaft 280. The tab 250interfits with the slot 260 of the vertical shaft 160 in order totransmit rotary motion of the vertical shaft 160 to the shuttle body290. The tab 250 may be free to slide vertically within the slot 260such that the lower shaft 280 and connected shuttle body 290 can movevertically independent of the vertical shaft 160. The lower shaft 280also includes an opposing pair of release ribs 320 for engaging with anopposing pair of release slots 330 formed in the valve body 210 when thestop-fill assembly 200 is in a closed position. A bearing clip 2314 maybe provided between the valve body 210 and the release ribs 320 toincrease the durability and decrease the friction of the contact betweenthe release ribs and the valve body. The bearing clip 2314 may becomposed of a metal, a low friction plastic, a polymer, or othersubstance.

The stop-fill assembly 1810 can transition between an open position anda closed position. In the open position, fluid (e.g., from the port 120)can flow through the stop-fill assembly 1810, while in the closedposition fluid is prevented from flowing through the stop-fill assembly1810.

In the open position, and under the pressure of incoming fluid pressingdownward on the shuttle body 290, the release ribs 320 of the valveshuttle 230 ride against the upper surface of the valve body 210 or thebearing clip 2314. Thus, the release ribs 320 keep the stop-fillassembly 200 open against the force of a fluid flow (e.g., from the port120). When the float arm 150 is rotated to the position correspondingwith an empty condition, the release ribs 320 are at 90 degree angles tothe slots 330, sitting on the upper surface of the valve body 210 sothat the valve shuttle body 290 cannot go down. In this configuration,fluid travels downward through the space between the upper shaft 240 andthe valve head 220, around the shuttle body 290 through ports 2340 andinto the container (e.g., tank 100).

FIG. 19B is a partial top view of the valve body 210 of FIG. 19A withrelease ribs 320 at 90 degree angles to slots 330, sitting on thesurface of valve body 210 (and bearing 2314) so that the valve shuttlebody is in the open position. FIG. 19C is a partial sectional andpartial cutaway view of the shuttle body 290 positioned in the valvebody of FIG. 19A. In the open position, fluid travels downward throughthe space between the upper shaft 240 and the valve head 220, around theshuttle body 290 and through discharge ports 2340 formed in valve body210 and into the container (e.g., tank 100.) In this variation, ports2340 direct fluid entering the tank through the stop-fill device 1810radially away from a central longitudinal axis of tank 100 and likewiseaway from shaft 160. Discharging fluids through radially directed ports2340 reduces the amount of turbulence generated in tank 100 during thefilling operation along with possible impingement of the fluid ontofloat 140 or float arm 150 which can interfere with the operation of thefloat.

As the vertical shaft 160 rotates due to the motion of the float arm150, the shuttle body 190 rotates and eventually rotates to the closedposition. When this happens, the downward pressure of the fluid flow,which is sufficient to overcome the opposing pressure of the spring 360,causes the release ribs 320 to drop through the bearing clip 2314 andinto the release slots 330. The shuttle body 290 then acts as a blockingmember. As shown in FIG. 24C, a beveled circumferential surface 2342 ofshuttle body 290 seats against a corresponding beveled surface or seat2344 of valve body 210 to block the flow of fluid through the stop-fillassembly 1810. Notably, the movement of shuttle body 290 when releaseribs 320 become aligned with release slots 330 is longitudinallyindependent of the rotation of vertical shaft 160. In other words, theshuttle body 290 can move up and down in the longitudinal direction eventhough the vertical shaft 160 is fixed in the longitudinal direction,while at the same time the shuttle body remains rotationally engagedwith the vertical shaft such that the shuttle body and vertical shaftalways rotate together. Thus, shuttle body 290 rotates in response tothe rotation of shaft 160, but translates longitudinally independent ofshaft 160 when moving between the open and closed positions.

In the embodiment shown, a separate spring clip 2312 is provided forstabilizing the spring 360 against the valve body 210 and for preventingbinding of the spring when the vertical shaft 160 rotates. Therelatively short distance that the shuttle body 290 travels when movinginto the closed position means that the vertical translation of themagnet 270 is also relatively small. Therefore the magnetic fieldproduced by the magnet 270 does not change substantially, and thus themovement of the magnet 270 along the axis of the stop-fill assembly 1810has no substantial bearing on the interaction of the magnet 270 and thepointer magnet 2152. It is the rotational movement of the magnet 270that produces a change in the magnetic flux field that may berecognizable by the dial 1815 as a change in the fluid level of the tank100.

Once the stop-fill assembly 1810 is in the closed position, filling ishalted. The source of the incoming fluid is disconnected from the port120 or the port 120 is closed. At this point, since there is no longerany pressure against the upper side of the valve shuttle body 290, thevalve shuttle body 290 is moved upward under the force of the spring 360so that the stop-fill assembly 1810 transitions to the open position.This allows for fluid or gas to exit the tank 100 by traveling back upthrough the stop-fill assembly 1810 to the port 120.

In some cases there may be relatively high pressures against the shuttlebody 290 due to the filling pressure and the fluid flow. The actualflotation or the buoyancy of the float 140 produces a relatively smalltorque, so friction between the release ribs 320 and the upper surfaceof the valve body 210 might be high and resist rotation of the shuttlebody 290. For this reason, as has been described, low fiction materialsmay be selected for the construction of the release ribs 320, valve body210, and other components. Furthermore a bearing clip 2314 may beemployed to both decrease friction and increase durability.Additionally, flow surfaces may be provided on the shuttle body 290 suchthat pressure of the incoming fluid assists in the rotation of the valveshuttle body 290. As has been described, the shape of the shuttle body290 may be chosen such as to assist in its own rotation.

FIG. 19D is a top view of an alternate valve body 2350 and FIG. 19E is apartial cutaway and partial sectional view of a corresponding shuttlebody 2352. In this variation, release ribs 320 have been replaced with apair of release arms 2354 that extend outward from an upper surface ofshuttle body 2352 and downward to a surface 2356 of valve body 2350outside of beveled valve seat 2344. A pair of release apertures 2358formed in surface 2356 receive the distal ends 2360 of arms 2354,permitting the shuttle body to move downward when arms 2354 are movedinto alignment with apertures 2358.

In the open position, ends 2360 of arms 2354 rest on surface 2356,holding shuttle body 2352 up so that fluid may past the shuttle bodythrough fill ports 410 and into the tank through radially directeddischarge ports 2340. As the vertical shaft 160 rotates due to themotion of the float arm 150, the shuttle body 2352 rotates andeventually rotates to the closed position. When this happens, thedownward pressure of the fluid flow, which is sufficient to overcome theopposing pressure of the spring 360, causes the ends 2360 of releasearms 2354 to drop into release apertures 2358. Shuttle body 2352 movesdown with beveled circumferential surface 2342 of shuttle body 2352seating against the corresponding beveled surface 2344 of valve body2350 to block the flow of fluid through the stop-fill assembly 1810.

FIG. 19F is a side view of an alternate float assembly 2380 for use withstop-fill assembly 1810. Float assembly 2380 includes a float arm 2382,a float 2384 attached to a first end of arm 2382 and a counterweight orcounterbalance 2386 attached to a second end of arm 2382. Float arm 2382is operatively connected to a sector gear 170 which drives pinion gear180 that is attached to vertical shaft 160.

In the embodiment illustrated in FIG. 19F, float 2384 is mounted on arm2382 such that the float is offset from the longitudinal axis of thefloat arm such that a longitudinal axis of the float extends below thefloat arm when the float arm is in a horizontal orientation. In oneembodiment, float 2384 is slanted downward at an angle α from about 10degrees to about 45 degrees relative to a longitudinal axis 2388 of arm2382. It was found that angling float 2384 relative to the longitudinalaxis of arm 2382 in this manner improved the efficiency of the float andincreased the sensitivity of the assembly to changes in liquid level intank 100 at near full volumes or at volumes where the angle of thelongitudinal axis 2388 of arm 2382 relative to horizontal approaches 90degrees. In another variation, float 2384 may be offset from thelongitudinal axis of arm 2384 by forming a bend in the arm between shaft160 and the float, offsetting the float on the arm or using an extensionof the arm that offsets the float.

FIG. 19G is a partial sectional view illustrating the stop-fill assembly1810 of FIG. 19A positioned in pressurized tank 100. As illustrated tank100 includes a cylindrical sidewall 102 defining a central axis 104extending therethrough, a generally semi-cylindrical top wall 106, agenerally semi-cylindrical bottom wall 108 and a shield 112 extending atleast partially around a service valve 2700 suitable for use inconnection with stop-fill devices described herein. In one embodiment,service valve 2700 includes a valve inlet/outlet 1802 through which tank100 is filled and emptied, a relief valve 2022, and a threaded tankconnection 1820 that is screwed into a threaded opening 122 in top wall106 of the tank. Typically, tank 100 will have only one such opening 122through which the tank is filled and emptied. Since tank 100 is filledand emptied through opening 122, stop-fill assembly 1810 must functionas a two way valve as described herein.

Referring still to FIG. 19G, a handle 1812 is provided for opening andclosing service valve 2700. Tank 100 is suitable for containing apressurized fluid 114 such as liquefied natural gas (LNG), liquefiedpropane and/butane and similar volatile liquefied gases commonly usedfor cooking and heating. Tank 100 may be filled with such liquefiedgases through service valve 2700 and stop-fill assembly 1810 whichblocks flow of the liquefied gas when the amount of fluid 114 reaches apredetermined level corresponding to a desired volume of pressurizedfluid 114 in tank 100 and then reopens when the fill source isdisconnected and pressure across the stop-fill assembly is equalizedsuch that spring 360 (FIG. 19A) forces shuttle body 290 upwardly,opening the stop-fill assembly. Gases 116 vaporized from pressurizedfluid 114 are released through service valve 2700 which is typicallyconnected to a gas grill, stove, heater or similar device with suitabletubing or pipe.

In the illustrated embodiment, pressurized fluid 114 entering tank 100flows through radially directed ports 2340 which direct fluid enteringthe tank away from longitudinal axis 104 of tank 100 in the direction ofarrows 124. In this manner, the amount of turbulence generated on thesurface of the fluid 114 in tank 100 during the filling operation isreduced. Possible direct impingement of fluid 114 onto float 140, floatarm 150 and/or counter balance 1825 is eliminated or substantiallyreduced. Reducing surface turbulence and/or impingement on the float armreduces the likelihood of premature activation of the stop-fill device.

Turning to FIG. 20A, a front view one embodiment of a dial assembly inaccordance with aspects of the present disclosure is shown. The dialassembly may be removable or it may be permanently affixed to theservice valve. A dial face 2610 may be molded plastic or anothersuitable material. A lens 2615 may be provided. The lens 2615 may beglass or plastic or another suitably transparent material. It can beseen that the lens 2615 provides protection for the pointer 2130 as wellas the indicator markings 2120. The indicator markings 2120 may bepainted or molded onto the dial face 2110. The pointer 2130 is driven byan internal magnet 2152 (FIG. 20B).

Referring now to FIG. 20B, a rear view of another embodiment of a dialassembly in accordance with aspects of the present disclosure is shown.Here the dial 2600 is shown from the rear and additional features can beseen. The dial assembly may be removable or it may be permanentlyaffixed to the service valve. Protruding from the dial face 2610 on thebackside is a pointer magnet housing 2150. The pointer magnet housing2150 provides clearance and covering for the magnet 2152 that drives thepointer 2130. In the embodiment shown, the pointer magnet housing 2150is substantially cylindrical although the present embodiment is notmeant to be so limited. In some cases the pointer magnet housing 2150may have other shapes or may only be generally convex so as to provideclearance for the magnet 2152. Some embodiments may also have one ormore stabilizer tabs 2622 protruding from predetermined locations on thebackside of the dial face 2610. The tab 2622 may be placed against oneor more features or surfaces of a service valve to provide stabilizationand proper orientation to obtain accurate readings from the dial 2600,as will be shown in greater detail below. The tabs may take on varioussizes and shapes according to the particular application of the dial2600. Some embodiments will provide affixment means to aid in anchoringthe dial 2600 into place on a service valve. One example of suchaffixment means is shown in FIG. 20B as wire anchors 2630. These are forillustration only as other means such as clamps, clips, tabs, snapfittings, adhesives, screws or other fasters, magnetics, or otherimplements could be used.

Referring now to FIG. 20C, a side view of another embodiment of aremovable dial in accordance with aspects of the present disclosure isshown. FIG. 20C illustrates the removable dial 2600 in profile. Here thevarious on the front and on the rear of the dial face 2610 can be seenin relation to one another.

Referring now to FIG. 20D-E, another rear view, and side view,respectively, of another embodiment of a removable dial in accordancewith aspects of the present disclosure is shown. FIGS. 20D-E illustratethe same dial 2600 as described in FIGS. 20A-C, but without havingstabilizer tabs 2622. It will be appreciated that not all embodimentswill require stabilizer tabs 2622. The shape and position of the magnethousing 2150 may provide sufficient anchorage for some embodiments.Additionally, the affixment means 2630 may also make the use ofstabilizer tabs 2622 unnecessary.

FIG. 21 is a side view of one embodiment of a service valve inaccordance with aspects of the present disclosure. The service valve2700 is suitable for use in a combination with the stop-fill devicesdescribed herein and with various dials as will be described. FIG. 21illustrates the presence of the valve outlet 1802, the relief valve2022, and the tank connection 1820. The service valve knob 1812 may beprovided to allow opening and closing of the service valve assembly 1805and may sit atop the valve body 2020. A wrench flat 2005 can be seen inFIG. 21. A pair of wrench flats may define parallel surfaces on theservices valve as better seen in FIG. 23 below. In one embodiment theservice valve 2700 is a standard, commercially available brass servicevalve. However, in other embodiments, other non-ferrous materials may beused to construct the service valve. The service valve 2700 may besuitable for use with a dial that does not require any modification tothe service valve 2700. Such configurations may be used in cases wherethe magnet 270 (e.g., FIGS. 18B-19) and/or dial magnet 2152 (e.g., FIG.20A-E) are strong enough to interact without the need for modificationto the wrench flat, or where the dial 2600 mounts to a location on theservice valve 2700 having a relatively thin wall such that strongermagnets are not required.

FIG. 22 is a side view of yet another embodiment of a service valve inaccordance with aspects of the present disclosure. FIG. 22 illustrates aservice valve 2800 that has had modifications to the wrench flat 2005.The service valve 2800 has a mounting feature 2802 that is partiallywithin the wrench flat 2005. The alignment feature 2802 may be a seat, arecess, a detent, or another feature that is partially within the wrenchflat 2802. Generally speaking, the alignment feature 2802 may be agenerally concave surface in a portion of the wrench flat 2005. Thealignment feature 2802 may be created by drilling, cutting, sanding, oranother machining method. The alignment feature 2802 could also be castdirectly into the service valve 2800 during manufacturing. The alignmentfeature 2802 may provide assistance in affixing a dial in the properlocation to interact with a magnet (e.g., magnet 270, FIG. 19) insidethe service valve 2800. The alignment feature 2802 may also allow themagnet 270 to come into suitably close proximity to the magnet housing2150 and magnet 2152 of the dial 2600 to allow proper readings.

Referring now to FIGS. 23A-B, rear views with partial cutaway showing anupper portion of a combination service valve, a stop-fill assembly, anda removable dial in accordance with aspects of the present disclosureare shown. From the view of FIG. 23A it can be seen that the servicevalve 2700 provides two unmodified wrench flats 2005 and 2205. Thewrench flats 2005 and 2205 may be used to aid in the insertion of thevalve assembly 1805 into a tank such as the tank 100 of FIG. 1. A lowerservice valve throat 2210 is shown in outline and provides throatthreads 2212.

From FIG. 23A, it can be seen how the various components of the assemblycombination of FIGS. 23A and 23B may be assembled. It can be seen thatthe dial 2600 provides a stabilizer tab 2622 (as in FIGS. 20B-C). Thetab 2622 may be employed to stabilize and locate the dial 2600 in aproper location to interact with the magnet 270. The dial 2600 may beplaced onto the service valve 2700 as shown by the arrow C and the lineC′. It can also be seen that the magnet 270 attached to the end of theupper shaft 240 is to be inserted into the lower service valve throat2210. In one embodiment, the threads 1910 of the valve head 220 may beadapted to interfit with the throat threads 2212 such that when themagnet 270 is inserted into the lower service valve throat 2210 as shownby the arrow D, the magnet 270 is in relatively close proximity to themagnet inside the pointer magnet housing 2150. In one embodiment, thestrength of the magnets 270 and 2152 are such that no machining orrecess is needed in the service valve 2700 is order to obtain effectivemagnetic coupling. Rotation of the magnet 270 about a generally verticalaxis (i.e., the axis of rotation of shaft 240) causes variations of theassociated flux field about the vertical axis. This flux field interactswith the flux field associated with the dial magnet 2152 to causerotation of the dial magnet about a generally horizontal axis (i.e., theaxis of rotation of the pointer 2130). Thus, a rotation of the magnet270 translates into movement of the pointer 2130. It can also be seenthat the rotation of the shaft 240 and magnet 270 is substantiallyorthogonal to the direction of rotation of the pointer 2130 and need notnecessarily be vertical and horizontal.

FIG. 23B shows the assembled combination of the service valve 1805, thedial 2600, and the stop-fill assembly 1810. It can be seen that the dial2600 is securely fastened to the service valve assembly 1805 by theaffixment means 2630. The affixment means 2630 and location thereof arefor illustration only. It will be appreciate that affixment means 2630and its location, other than that shown, are possible depending upon thespecific configuration of the service valve 2700 and other componentsand the needs of the user. It will also be appreciated that dependingupon the affixment means 2630 chosen, that the dial 2600 may be mountedin removable or permanent fashion. In the embodiment shown, the tab 2622rests against the surface of the valve body 2020 and the wrench flat2005. Thus, rotational and vertical stabilization of the dial 2600 areprovided. As can be seen in the cutaway, the magnet 270 is rotatableproximate the pointer magnet housing 2150. As the magnet 270 rotates inresponse to movements of the float 140, such movements may be indicatedon the face of the dial 1815 via magnetic interaction between the magnet270 and the magnet 2152 contained within the dial 1815.

FIGS. 24A-B are rear views with partial cutaway showing an upper portionof a combination service valve, a stop-fill assembly, and a removabledial in accordance with aspects of the present disclosure. From the viewof FIG. 30A it can be seen that the service valve 2800 provides twowrench flats 2005 and 2205. The wrench flats 2005 and 2205 may be usedto aid in the insertion of the valve assembly 1805 into a tank such asthe tank 100 of FIG. 1. The recess mounting feature 2802 is also shownin dotted line within the wrench flat 2005. A lower service valve throat2210 is shown in outline and provides throat threads 2212.

From FIG. 24A, it can be seen how the various components of the assemblycombination of FIGS. 24A and 24B may be assembled. It can be seen thatthe dial 2600 may be attached to the service valve 2800 by placing thepointer magnet housing 2150 against the valve stem 2020 as guided by thealignment feature 2802 as shown by the arrow E and the dotted line E′.The alignment feature provides a guide for the proper location of thedial 2600 again the valve stem 2020 and may also provide rotationalstabilization of the dial 2600 depending upon the shape of the magnethousing 2152 and the mounting feature 2802.

It can also be seen that the magnet 270 attached to the end of the uppershaft 240 can be inserted into the lower service valve throat 2210. Inone embodiment, the threads 1910 of the valve head 220 may be adapted tointerfit with the throat threads 2212 such that when the magnet 270 isinserted into the lower service valve throat 2210 as shown by the arrowF, the magnet 270 is in relatively close proximity to the magnet insidethe dial magnet housing 2150. Rotation of the magnet 270 about agenerally vertical axis (i.e., the axis of rotation of shaft 240) causesvariations of the associated flux field about the vertical axis. Thisflux field interacts with the flux field associated with the dial magnet2152 to cause rotation of the dial magnet about a generally horizontalaxis (i.e., the axis of rotation of the pointer 2130). Thus, a rotationof the magnet 270 translates into movement of the indicator pointer2130. It can also be seen that the rotation of the shaft 240 and magnet270 is substantially orthogonal to the direction of rotation of thepointer 2130 and need not necessarily be vertical and horizontalrotation.

FIG. 24B shows the assembled combination of the service valve 2800, thedial 2600, and the stop-fill assembly 1810. It can be seen that the dial2600 is securely fastened to the service valve assembly 1805 by theaffixment means 2630. The affixment means 2630 and location thereof arefor illustration only. It will be appreciated that affixment means 2630and its location, other than that shown, are possible depending upon thespecific configuration of the service valve 2800 and other componentsand the needs of the user. It will also be appreciated that dependingupon the affixment means 2630 chosen, that the dial 2600 may be mountedin removable or permanent fashion. In the embodiment shown, the magnethousing 2152 rests against the valve stem and the alignment feature2802. Thus, vertical, and possibly rotational, stabilization of the dial2600 are provided. The affixment means 2630 may also providestabilization. As can be seen in the cutaway, the magnet 270 isrotatable proximate the pointer magnet housing 2150. As the magnet 270rotates in response to movements of the float 140, such movements may beindicated on the face of the dial 2600 via magnetic interaction betweenthe magnet 270 and the magnet 2152 contained within the dial 2600.

FIG. 25 is a diagram illustrating one possible correlation between themagnetic field produced by an indicator magnet and a dial readingaccording to aspects of the present disclosure. Relative fieldintensities (in both N and S) and directions correspondent to degrees ofrotation of the magnet 270 from a starting point are labeled forillustration. Referring also back to FIGS. 18A-B and 19A, it can be seenthat the orientation of the magnet 270 changes in response to a level ofthe float 140 on the float arm 150. The magnet 270 will have a northpole and a south pole and will produce a magnetic field in proximitythereto that will vary in strength and direction. The float arm 150 andpinion gear 180 can be configured to provide a rotation of the magnet270 starting from a known position (e.g., empty) and proceeding toanother known position (e.g., full) in a known ratio. Thus the magneticfield direction and strength produced by the magnet 270 as it takes onvarious propositions between open and closed can be known and used tocalibrate a dial 1815 or magnetic field sensor 2310. The diagram of FIG.25 illustrates that in one embodiment, only a portion of the fieldstrengths and directions possible from the magnet 270 may be used inorder to simplify calibration and readings. The direction (e.g., northor south) and relative field strength produced in known location nearthe magnet 270 as it is rotated in graphed. It can be seen that withinparticular range R, the magnetic field strength and direction takes oneach possible value or a subset of possible values only once. Byselection of the gearing ratio of the gears 170 and 180 and the size andshape of the float art 150 and float 140, the range R, or in the presentembodiment, subset thereof, G, may be used over the range of possiblefluid levels in the container (e.g., tank 100). Possible markings for agauge dial or other indicator corresponding to the field values over therange G are shown in FIG. 25 for illustration.

Referring now to FIG. 25A, a side view 2900 of the spatial relationshipbetween a gauge magnet and a dial magnet according to aspects of thepresent disclosure is shown. The diagram 2900 could correspond to therelationship between the magnet 270 and the pointer magnet 2152 when inuse with any of the gauge and dial combinations described herein,whether a stop-fill device is included in the combination or not. It canbe seen that the magnet 270 attached to the upper shaft 240 and rotatesabout the axis 2910 of the shaft 240. As the magnet 270 rotates, a plane2912 is defined. In the two-dimensional view of FIG. 29, the plane 2912is represented in dotted line. As has been described, a rotation of themagnet 270 about its axis 2910 causes a corresponding rotation of thepointer magnet 2152 about its axis 2914. It can be seen here that theaxes 2910 and 2914 are generally orthogonal. In some embodiments orapplications, one axis will be vertical while the other is horizontalbut this is not required. However, in some embodiments, an offsetbetween the plane of rotation 2912 of the magnet 270 and the axis 2914of rotation of the pointer magnet 2152 will be provided. This allowsincreased leverage in the magnetic flux between the magnets 270 and 2152to ensure adequate rotation of the pointer magnet 2152 by the magnet270. The offset can vary by application and depending upon the range ofmotion needed in the pointer 2130. The offset could also be in eitherdirection, i.e., above or below the axis 2914 along the shaft axis 2910.

FIG. 26 is a partial section, partial cut-away view of a combinationgauge and stop-fill valve assembly 3000 suitable for use with a tanksuch as tank 100 (FIG. 19G) containing a pressurized fluid such asliquefied natural gas (LNG), liquefied propane and/butane and similarvolatile liquefied gases commonly used for cooking and heating.Stop-fill valve assembly 3000 includes a valve body 3002 and acylindrical valve head 3004 configured to extend into the lower throat3006 of a service valve 3008. Valve head 3004 and throat 3006 may beprovided with threads (not shown) for connecting stop-fill assembly 3000to the service valve. A support member 3010 extends downwardly fromvalve body 3002 with a vertical shaft 3012 rotatably disposed within thesupport member. A float arm 3014 is connected to the distal end ofsupport member 3010 for rotation about the distal end of the supportmember in response to changes in the fluid level in tank 100.

A float 3016 is connected to a first end of float arm 3014 with acounterbalance 3018 attached to a second end of the float arm remotefrom the float. Float 3016 moves in response to changes in the fluidlevel in tank 100, causing float arm 3014 to rotate around the distalend of support member 3010. Rotation of float arm 3014 is transmitted tovertical shaft 3012 by means of a sector gear 3022 attached to the floatarm that engages a pinion gear 3024 mounted on the distal end ofvertical shaft 3012 to rotate the shaft. The upper or proximate end ofvertical shaft 3012 engages valve shuttle 3026, e.g., by means of thetab-and-slot arrangement shown in FIG. 19A, to rotate the shuttle inresponse to changes in the fluid level in tank 100.

As best illustrated in FIGS. 26A and 26B, valve body 3002 includes fillports 3020 that communicate with radial ports 3076 to allow fluid toflow into and out of tank 100. In one variation, radial ports 3076 aredirected radially away from and generally perpendicular to thelongitudinal axis of support member 3010 to direct fluid entering tank100 away from float 3016, float arm 3014 or counterbalance 3018. Theradial orientation of ports 3076 prevents or minimizes impingement offluid entering tank 100 on float 3016, float arm 3014 or counterbalance3018 and/or turbulence that may interfere with the operation ofstop-fill assembly 3000.

Referring to FIGS. 27 and 30, valve shuttle 3026 includes an upper shaft3028 with a magnet holder 3031 formed on the distal end of the uppershaft, a shuttle body 3032 and a lower shaft 3034. Upper and lowershafts 3028, 3034 each extend along a longitudinal axis 3036 of valveshuttle 3026. Shuttle body 3032 includes a generally conical upper wall3033 with a plurality of ribs 3038 extending outwardly from the upperwall. A pair of release ribs 3030 extend radially outward from theproximate end of lower shaft 3034 and downwardly from shuttle body 3032.Release ribs 3030 bear against valve body 3002 to support valve shuttle3026 when stop-fill assembly 3000 is in the open position. A tab 3040formed at the distal end of lower shaft 3034 engages a correspondingslot 3042 formed in the upper end of vertical shaft 3012 to transmitrotation (but not vertical motion) of the vertical shaft to valveshuttle 3026. A spring 3044 disposed around the proximate end ofvertical shaft 3012 biases valve shuttle 3026 upwardly away from thevertical shaft. A spring clip 3046 prevents spring 3044 from binding asvertical shaft 3012 and shuttle body 3032 rotate.

As best illustrated in FIG. 27 valve shuttle 3026 is disposed on valvebody 3002 with upper shaft 3028 positioned in valve head 3004. Shuttlebody 3032 is positioned inside a valve chamber 3048 including an upper,generally conical wall 3050, a cylindrical side wall 3052 and a bottomwall 3054. In one variation, ribs 3038 act as stops, limiting upwardtravel of shuttle body 3032 in valve chamber 3048 by contacting conicalwall 3050 of the chamber. As best illustrated in FIG. 32, a passage 3056formed through bottom wall 3054 has opposed release slots 3058 extendingtherefrom for receiving release ribs 3030 when valve shuttle 3026rotates to a position where the release ribs are aligned with therelease slots. Lower shaft 3034 extends through a central portion ofpassage 3056 to engage the proximate end of vertical shaft 3012. Abeveled sealing surface or valve seat 3060 formed in bottom wall 3054seals against a corresponding beveled sealing surface 3062 (FIG. 30)that extends circumferentially around the lower edge of shuttle body3032 when shuttle body 3032 translates into the closed position. In onevariation, the distance between valve seat 3060 and sealing surface 3062when stop-fill assembly 3000 is in the open position may be determinedby the length of release ribs 3030 that support valve shuttle 3026.

Referring to FIGS. 26 and 27, stop-fill assembly 3000 operates inessentially the same manner as described in connection with embodimentsdisclosed above. Service valve 3008 is connected to a source of LNG orLPG and opened. The LPG flows through service valve 3008 into an annularspace 3064 between valve head 3004 and upper shaft 3028 and into valvechamber 3048. The LPG flows around shuttle body 3032, between valve seat3060 and sealing surface 3062 and through fill ports 3020, discharginginto tank 100 through radial ports 3076. As tank 100 fills, liftingfloat 3016, float arm 3014 rotates around the distal end of supportmember 3010. Sector gear 3022 rotates with float arm 3014, turningpinion gear 3024 and vertical shaft 3012. Valve shuttle 3026 rotateswith vertical shaft 3012 until release ribs 3030 move into alignmentwith release slots 3058. When release ribs 3030 are aligned with releaseslots 3058, the downward force on valve shuttle 3026 exerted by LPGflowing over shuttle body 3032 overcomes the biasing force of spring3044, causing the shuttle to translate longitudinally with the releaseribs entering the release slots. Sealing surface 3062 of shuttle body3026 moves into abutment with valve seat 3060, closing off the flow ofLPG through stop-fill assembly 3000. When service valve 3008 is closedand/or the downward force on valve shuttle 3026 removed, spring 3044pushes the valve shuttle up, returning the valve to the open position.

Stop-fill valve 3000 relies on the force exerted on valve shuttle 3026to close the valve when a fluid in the tank such as LNG or LPG reaches apredetermined level, for example 80% of the capacity of the tank. Theforce applied to valve shuttle 3026 is therefore dependent upon the rateof fluid flow and the differential pressure across the valve. However,LPG is a volatile material having a vapor pressure that variesconsiderably with temperature. For example the vapor pressure of 100%propane varies from 24.5 psig at 0 degrees F. to approximately 177 psigat 100 degrees F. Consequently, the pressure differential acrossstop-fill valve 3000 when filling tank 100 with LPG may varyconsiderably depending upon factors such as ambient temperature, pumppressure and the composition of the LPG (e.g., % propane). In view ofthese variations, it is desirable that stop-fill valve 3000 closequickly and reliably at relatively low differential pressures across thevalve.

Referring now to FIGS. 28, 29 and 32, in one variation, stop-fill valve3000 is configured with a maximum upper flow area 3070 when the valve isin the open position. As best illustrated in FIG. 29, upper flow area3070 is the cross-sectional area between conical upper wall 3033 ofshuttle body 3032 and conical wall 3050 of valve chamber 3048 takenalong line 29-29 of FIG. 27. As illustrated in FIG. 28, a lower flowarea 3072 is the area between valve seat 3060 of valve body 3002 and thecorresponding sealing surface 3062 of shuttle body 3032 when the valveis in the open position. The size of lower flow area 3072 may beincreased or decreased by adjusting the length of release ribs 3030which support valve shuttle 3026 when stop-fill valve 3000 is in theopen position. Referring to FIG. 31, a swept surface area 3074corresponds to the surface area of the conical upper wall 3033 ofshuttle body 3032.

It was found that restricting the flow through between shuttle body 3032and valve seat 3060 by reducing the area of lower flow area 3072increased the speed at which the valve closed. For example, it wasdetermined that reducing lower flow area 3072 from 0.065 square inchesto 0.0445 square inches, a thirty two percent reduction, significantlyincreased the speed at which the valve closed when tested with water ata differential pressure of about 10 psig. In this example, upper flowarea 3070 was increased from about 0.122 square inches to 0.1305 squareinches, a seven percent increase and the swept surface area decreasedfrom 0.086 square inches to 0.079 square inches, a decrease of aboutnine percent.

Thus, in one variation, the ratio of the upper flow area 3070 to thelower flow area 3072 is approximately 1.8 to about 3.5 with the ratio ofthe swept surface 3074 to the lower flow area 3072 ranging from about1.3 to about 2.5. In a preferred variation, the ratio of the upper flowarea 3070 to the lower flow area 3072 is approximately 2.5 to about 3.0with the ratio of the swept surface 3074 to the lower flow area 3072ranging from about 1.5 to about 2.0. Most preferably, the ratio of theupper flow area 3070 to the lower flow area 3072 is approximately 2.9with the ratio of the swept surface area 3074 to the lower flow area3072 approximately 1.8.

The drawings and detailed description herein are to be regarded in anillustrative rather than a restrictive manner, and are not intended tolimit the following claims to the particular forms and examplesdisclosed. On the contrary, further modifications, changes,rearrangements, substitutions, alternatives, design choices, andembodiments will be apparent to those of ordinary skill in the art.Thus, it is intended that the following claims be interpreted to embraceall such further modifications, changes, rearrangements, substitutions,alternatives, design choices, and embodiments

1. A combination tank valve apparatus providing fluid flow control,overfill protection, and fluid level gauging for use on a storage tankfor liquefied gas, the storage tank having an internally threaded outletport, the apparatus comprising: a service valve having a body defining atank connection, a valve seat, a valve outlet, and a pair of wrenchflats; the tank connection having external threads formed thereonadapted for threaded connection into the outlet port of the tank, anddefining an internal passage including a throat disposed on a first sideof the valve seat and connected to a lower port; the valve outletdefining an internal passage disposed on a second side of the valve seatand connected to an outlet port; the wrench flats projecting fromopposite exterior sides of the body adjacent to the throat to definesubstantially flat surfaces oriented parallel to one another; anoverfill protection device mounted to the tank connection of the servicevalve and including a float, a shaft, a overfill valve, and a shaftmagnet, the float adapted to float at the liquid/gas interface of aliquefied gas in the tank; the shaft operably connected to the float torotate in response to changes in the position of the float and having anupper portion extending into the throat of the service valve; theoverfill valve operably connected to the shaft to transition betweenopened and closed configurations when the shaft rotates into apredetermined position; the shaft magnet firmly mounted to the upperportion of the shaft within the throat of the service valve between thevalve seat and the wrench flats to rotate with the shaft about a firstaxis and having a first magnetic flux field extending therefrom; and adial mounted on the body of the service valve and having a body, a dialmagnet, and a pointer; the body having a dial magnet housing extendingtherefrom with at least a portion of the dial magnet housing disposedadjacent to the body between the wrench flat and the valve seat; thedial magnet being rotatably mounted in the dial magnet housing to rotateabout a second axis oriented substantially orthogonal to the first axisand having a second magnetic flux field extending therefrom and at leastpartially overlapping the first magnetic flux field, the first andsecond magnetic flux fields interacting to cause rotation of the dialmagnet about the second axis in response to rotation of the shaft magnetabout the first axis; the pointer being mounted on the dial magnet torotate with the dial magnet and provide a visual indication of theliquid level within the tank.
 2. The combination of claim 1, wherein thedial has a spring clamp for attaching to the service valve.
 3. Thecombination of claim 1, wherein the overfill protection device providesa first set of threads adapted to interfit with a second set of threadson the interior of the tank port of the service valve.
 4. Thecombination of claim 1, wherein the service valve body is substantiallyconstructed of a non-ferrous material.
 5. The combination of claim 4,wherein the non-ferrous material of the service valve body is selectedfrom the group consisting of brass, aluminum, zinc and stainless steel.6. The combination of claim 1, wherein the overfill protection device issubstantially constructed of a hydrocarbon-resistant material.
 7. Thecombination of claim 6, wherein the overfill protection device issubstantially plastic.
 8. The combination of claim 7, wherein theplastic of the overfill protection device is selected from the groupconsisting of acetal, nylon and ultem.
 9. The combination of claim 1,wherein the dial is removably mounted on the body of the service valve.10. The combination of claim 1, wherein the dial is permanently mountedon the body of the service valve.
 11. The combination of claim 1,wherein the dial is calibrated with at least markings corresponding toempty, one-half, and full.
 12. The combination of claim 1 furthercomprising a spring for biasing the valve in the open position such thatfluid can move out of the tank when the tank is substantially full. 13.A method of filling a pressurizable tank, comprising: positioning a tankhaving a cylindrical sidewall defining a central axis extendinglongitudinally therethrough with the central axis of the tank orientedin a generally vertical direction; directing the fluid through astop-fill assembly positioned at least partially inside the tank, thestop-fill assembly including a shuttle body, a valve body, and a floatoperatively connected to the shuttle body, the shuttle body operable toengage the valve body and block the flow of fluid into the tank, thevalve body directing the fluid radially away from the central axis ofthe cylinder at a location above the float when the shuttle body is inthe open position; operating the shuttle body with the float to engagethe shuttle body with the valve body and block fluid flow into the tankwhen the fluid level in the tank reaches a predetermined level.
 14. Themethod of claim 13 wherein the stop-fill assembly further comprises aspring that biases the shuttle body in an open configuration, the methodfurther comprising biasing the operating the shuttle body with thespring to move the shuttle body into the open position.
 15. The methodof claim 13 wherein fluid enters the tank through a service valveconnected to the top of the tank, the method further comprising:connecting the service valve to a source of pressurized fluid; openingthe service valve to admit fluid into the tank; and closing the servicevalve when the fluid level in the tank reaches the predetermined level.16. The method of claim 13 wherein the float is connected to acounterbalance with a float arm having a rotating connection with ashaft connected to the shuttle body and wherein the step of operatingthe shuttle body with the float comprises rotating the shuttle body withthe float arm to move the shuttle body into engagement with the valvebody.
 17. The method of claim 13 wherein the step of directing the fluidradially away from the central axis of the cylinder further comprisesdirecting the fluid through a least one port in the valve body thatextends radially away from a longitudinal axis of the shaft.
 18. Themethod of claim 17 further comprising the step of displaying the fluidlevel in the tank with a dial indicator operatively coupled to thefloat.
 19. The method of claim 17 further comprising the step ofdisplaying the fluid level in the tank with a dial indicator mounted onthe service valve.
 20. An overfill protection device for use with apressurizable tank having a cylindrical sidewall defining a central axisextending longitudinally therethrough, a generally semi-hemisphericalbottom wall and a generally semi-hemispherical top wall, comprising: afloat adapted to float at the liquid/gas interface of a liquefied gas inthe tank; a shaft operably connected to the float to rotate in responseto changes in the position of the float and having an upper portionextending into the throat of a service valve mounted the tank; anoverfill valve operably connected to the shaft to transition betweenopened and closed configurations when the shaft rotates into apredetermined position, the overfill valve further comprising at leastone outlet port directed radially outward relative to the central axisof the tank, wherein fluid entering the tank through the overfill valveis directed radially away from the central axis of the tank; a shaftmagnet firmly mounted to the upper portion of the shaft within thethroat of a service valve connected to the tank to rotate with the shaftabout a first axis and having a first magnetic flux field extendingtherefrom; and a dial mounted on the body of the service valve andhaving a dial magnet, and a pointer; wherein the dial magnet isrotatably mounted in the dial magnet housing to rotate about a secondaxis oriented substantially orthogonal to the first axis and having asecond magnetic flux field extending therefrom and at least partiallyoverlapping the first magnetic flux field, the first and second magneticflux fields interacting to cause rotation of the dial magnet about thesecond axis in response to rotation of the shaft magnet about the firstaxis; wherein the pointer being mounted on the dial magnet to rotatewith the dial magnet and provide a visual indication of the liquid levelwithin the tank.
 21. The device of claim 20 further comprising a floatarm for mounting the float; and a counterbalance mounted on the floatarm; wherein, the float arm is rotatably connected to the between thefloat and the counterbalance to rotate the shaft in response to movementof the float.
 22. The device of claim 20 further comprising a springbiasing the overfill valve into the open configuration such that theoverfill valve returns to the open configuration after the tank has beenfilled.